Found drain line was standing full. Pulled toilet and ran large drain machine. Did not locate blockage. I checked drain line under home and proceeded to check septic tank to find it full. I advised home owner to contact Layman’s to have it pumped out. A full septic can cause back up and plug vents so I advised customer to call us back if problems persist after septic is emptied. Note: toilet in master bath needs a repair flange. I secured tank using wood screw and washer. Customer advised same.